From H. W. Smyth, Greek Grammar, I §§149-188
GENERAL PRINCIPLES, ANASTROPHE, CHANGE OF ACCENT IN DECLENSION, INFLECTION AND COMPOSITION, PROCLITICS, ENCLITICS
181. Enclitics (from ἐγκλί̄νω lean on, upon) are words attaching themselves closely to the preceding word, after which they are pronounced rapidly. Enclitics usually lose their accent. They are:
a. The personal pronouns μοῦ, μοί, μέ; σοῦ, σοί, σέ; οὗ, οἷ, ἕ, and (in poetry) σφίσι.
b. The indefinite pronoun τὶς, τὶ in all cases (including τοῦ, τῷ for τινός, τινί, but excluding ἄττα ̂ τινά); the indefinite adverbs πού (or ποθί), πῄ, ποί, ποθέν, ποτέ, πώ, πώς. When used as interrogatives these words are not enclitic (τίς, τί, ποῦ (or πόθι), πῇ, ποῖ, πόθεν, πότε, πῶ, πῶς).
c. All dissyllabic forms of the present indicative of εἰμί am and φημί say (i.e. all except εἶ and φῄς).
d. The particles γέ, τέ, τοί, πέρ; the inseparable -δε in ὅδε, τοσόσδε, etc.
N. – Enclitics, when they retain their accent, are called orthotone.
182. The accent of an enclitic, when it is thrown back upon the preceding word, always appears as an acute: θήρ τε (not θῆρ τε) from θήρ ̈ τέ.
183. The word preceding an enclitic is treated as follows:
a. An oxytone keeps its accent, and does not change an acute to a grave: δός μοι, καλόν ἐστι.
c. A proparoxytone or properispomenon receives, as an additional accent, the acute on the ultima: ἄνθρωπός τις, ἄνθρωποί τινες, ἤκουσά τινων; σῶσόν με, παῖδές τινες.
d. A paroxytone receives no additional accent: a monosyllabic enclitic loses its accent (χώρᾱ τις, φίλος μου), a dissyllabic enclitic retains its accent (χώρᾱς τινός, φίλοι τινές) except when its final vowel is elided.
N. – Like paroxytones are treated properispomena ending in ξ or ψ when followed by a dissyllabic enclitic: κῆρυξ ἐστί; and so probably κῆρυξ τις.
e. A proclitic takes an acute: ἔν τινι, εἴ τινες.
Reference address : https://www.ellopos.net/elpenor/lessons/greek-accentuation.asp?pg=10